创建嵌套的XML节点

import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.DocumentBuilder;
import org.w3c.dom.Document;
import org.w3c.dom.Element;

public class CreateNestedXML {
    public static void main(String[] args) {
        try {
            // 创建DOM解析器工厂
            DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
            DocumentBuilder builder = factory.newDocumentBuilder();

            // 创建XML文档对象
            Document document = builder.newDocument();

            // 创建根节点
            Element rootElement = document.createElement("root");
            document.appendChild(rootElement);

            // 创建子节点
            Element childElement = document.createElement("child");
            rootElement.appendChild(childElement);

            // 创建孙子节点
            Element grandchildElement = document.createElement("grandchild");
            childElement.appendChild(grandchildElement);

            // 将XML文档转换为字符串输出
            String xmlString = documentToString(document);
            System.out.println(xmlString);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    // 将XML文档转换为字符串
    private static String documentToString(Document document) throws Exception {
        TransformerFactory transformerFactory = TransformerFactory.newInstance();
        Transformer transformer = transformerFactory.newTransformer();
        StringWriter writer = new StringWriter();
        transformer.transform(new DOMSource(document), new StreamResult(writer));
        return writer.getBuffer().toString();
    }
}